An estimated 25,000 cancers associated with the human papillomavirus (HPV) occurred annually in 38 states and the District of Columbia between 1998 and 2003, new research suggests. The study is one of 22 new reports coordinated by the CDC to assess the burden of HPV-associated cancers in the United States prior to the introduction of the HPV vaccine Gardasil. The vaccine protects against the two HPV types responsible for 70 percent of cervical cancers and the two types that cause 90 percent of genital warts.

Cervical cancer is the most common HPV-associated cancer, with nearly 11,000 cases in the United States per year. But HPV, which includes more than 100 different types, is also associated with cancers of the vulva, vagina, penis, anus, oral cavity, and oropharynx. (FDA recently expanded its approval of Gardasil to include prevention of vaginal and vulvar cancers.)

The estimates of HPV-associated cancers in the period before the HPV vaccine will give researchers baseline data for measuring the impact of the vaccine and cervical-cancer screening programs in reducing the incidence of cervical cancer and other HPV-associated cancers and precancers, according to Dr. Mona Saraiya of the CDC, who coordinated the studies.

Dozens of investigators authored the 22 articles for project ABHACUS (Assessing the Burden of Human Papillomavirus-Associated Cancers). A range of HPV-cancer related issues, including racial disparities, behavioral risk factors, and cancer mortality, are addressed in the studies.

The results, for instance, confirm recent reports showing higher rates of cervical cancer among black and Hispanic women and women in parts of the South. The mortality data on cervical cancer, one study concludes, are a reminder of the importance of screening and prevention programs, because during each year of the study more than 4,000 women died from this largely preventable disease.